The U.S. FDA approved Nitisinone for a rare metabolic disorder disease called hereditary tyrosinemia type 1 and alkaptonuria on January 18, 2002. It belongs to the family class known as enzyme inhibitors.

This medicine is used to treat a rare disease called hereditary tyrosinemia type 1 (adults, adolescents, and children of all ages) and alkaptonuria (adults). It works by blocking the breakdown of the amino acid tyrosine and preventing the accumulation of harmful substances.

Take the Nitisinone as your physician advises. Usually, this capsule will be taken once a day. Do not crush, chew, or open the medicine. Your physician will decide the correct dosage and duration based on age, body weight, and disease condition. Only stop taking the capsule if your doctor advises you to stop.

The most common side effects of Nitisinone are elevated levels of tyrosine, reduced platelet count, decreased lymphocyte count, conjunctivitis (eye inflammation), corneal opacity (clouding of the cornea), photophobia (sensitivity to light), eye irritation (keratopathy), eyelid inflammation, cataract (clouding of the eye's lens), reduced granulocyte count, itching.

Nitisinone should not be consumed if you are allergic to Nitisinone or any of its ingredients in the medication. Before taking this medicine, it is important to consult with your doctor. Inform your doctor if you have or have a history of any liver or kidney conditions. Notify your doctor if you have leukopenia (reduced WBC in the blood) or thrombocytopenia (reduced plated count in the blood). Your doctor will monitor platelet and white blood cell counts before initiating the treatment. 

During the treatment, regular eye examinations will be conducted to monitor for any potential effects on the eyes. Blood samples will be taken to assess the treatment's effectiveness and detect any possible blood disorders. Regular liver check-ups will be performed if you receive Nitisinone for hereditary tyrosinemia type 1. Follow-up appointments with your doctor every six months are recommended, and shorter intervals may be necessary if you experience any side effects.

It is important to continue taking the medicine as directed by your doctor and avoid doubling the dose to compensate for a missed dose. Liver and kidney patients should take Nitisinone cautiously and inform their doctor about all the underlying medical conditions. 

Dose adjustments will be made based on age, weight, and underlying medical conditions. Do not breastfeed while taking Nitisinone. Notify your doctor if you experience any serious side effects. Contact your doctor for more information.

1. LogixX Pharma Ltd, Electronic Medicines Compendium (EMC), [Revised on December 2022] [Accessed on 1st June 2023], pil.14734.pdf (medicines.org.uk)
2. Apotek Produktion & Laboratorier, US Food and Drug Administration, [ Revised on November 2021] [ Accessed on  1st June 2023], https://www.orfadin.com/pdf/full-prescribing-information.pdf
3. European medicines agency, [ Accessed on  1st June 2023], Orfadin | European Medicines Agency (europa.eu)

The drug information on this page is not a substitute for medical advice. It is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you are eligible to receive this treatment.